The leader of Spain’s Socialist party is busy travelling the country, giving speeches and interviews, smiling, rallying, hugging and doing all the other things politicians do in an election campaign. Yet the confidence is gone, as is the requisite optimism. If the polls are right, Mr Sánchez is on course to lead his party to yet another painful defeat on June 26.

This time, however, Spain’s Socialist Workers’ Party (PSOE) looks likely to be beaten not just by the centre-right Popular party but also by the far-left Unidos Podemos movement. According to recent surveys, the once mighty PSOE will come a distant third in this month’s general election, with just 20 per cent of the vote. Not only will it not lead the next government. Barring an unlikely late surge, it will not even lead the Spanish left.

The decline of the PSOE is, of course, part of a broader story. In Germany, the Social Democrats are polling around historic lows, as are the French Socialists under their unpopular president. Pasok has turned into a splinter group in the Greek parliament. In the UK, meanwhile, the venerable Labour party has undergone something of a reverse takeover, and is currently led by a politician who spent his entire career on the party’s leftist fringe. With few exceptions — Italy being the most obvious — the European centre-left finds itself in the midst of a long and painful retreat.

The Spanish case is interesting for two reasons. The first is that the PSOE has played an outsized role in national politics since the end of the Franco dictatorship, ruling Spain for 21 out of 39 years. That success reflects not least the fact that Spanish society tends towards the left: polls consistently find that the average voter is slightly left of centre. More than 32 per cent of respondents in a recent CIS poll identified as Socialists, Social Democrats or Progressives — while only 18 per cent referred to themselves as Conservatives or Christian Democrats. If the Socialists can’t make it here, can they make it anywhere?

The second reason is that Spain offers a textbook example of the travails that have befallen the centre-left. Call it a crisis of representation. Call it a capitulation to neoliberalism. Call it horribly unfair. The fact is that in Spain and elsewhere in Europe, voters have come to associate the centre-left with many of the (unpopular) policies traditionally championed by the right: austerity, deregulation, liberalisation, free trade.

In Spain, the defining moment of that trend came in 2011, when the previous Socialist government sought to appease the markets by writing a deficit cap into the constitution.

Coupled with a battery of austerity measures and budget cuts adopted by the same government, the constitutional amendment convinced many of the PSOE’s core voters that the party had lost its way.

They saw — rightly or wrongly — that the party of the welfare state, of the public sector and of the blue-collar worker had turned its back on all three. They saw their jobs disappear by the millions, and yet there was no one around to even articulate their fear and their anger and their frustration. Socialist leaders thought they were simply bowing to reality. But along the way they left millions of core supporters without a voice.

That was the vacuum into which Podemos was launched in January 2014, and that was filled by Syriza in Greece and by Jeremy Corbyn in the UK Labour party last year. The choice today for Europe’s centre-left is stark, says Mark Leonard, the director of the European Council on Foreign Relations: “Either you are wiped out by Podemos or you become Podemos.”

Mr Sánchez himself did a decent job of keeping the PSOE relevant in the months since Spain’s inconclusive general election last December. But his political space has shrunk dramatically. He is stuck between a centre-right that promises tax cuts and more supply-side reforms, and a new left that calls for an end to austerity and that credibly channels the anger on the streets. It is a dilemma that Mr Sánchez looks unlikely to resolve — and that could haunt Europe’s centre-left for many years to come.

We are travelers on a cosmic journey, stardust, swirling and dancing in the eddies and whirlpools of infinity. Life is eternal. We have stopped for a moment to encounter each other, to meet, to love, to share.This is a precious moment. It is a little parenthesis in eternity.